Oye vey, another Christian who is unaware how Jews interpret Zechariah 12:10. Here's are several sites explaining the original take on that:
http://www.geocities.com/Heartland/Prairie/1551/prophets/zech1210.htm
http://www.messiahtruth.com/zec1210.html
http://www.messiahtruth.com/zech12.html
http://www.jewsforjudaism.org/web/faq/faq084.html
"In summary, the Jewish perspective on Zechariah 12:10 is that it may be viewed as either an historical event that occurred in the prophet's time or, alternatively, as a messianic prophecy that is yet to be fulfilled. Neither of these interpretations agrees with, nor can accommodate, the Christian view that it is a messianic prophecy that was historically fulfilled with the death of Jesus."
I found myself reading what I wrote that led you to respond. The passage is a future event, not fulfilled yet, but will be after the nations come together in the Land against the Nation of Israel ( a regathered Jewish people).
Some of what is written on those links goes to great lengths to explain away things and if we had a long time to discuss them, we would. There is simply too much info there for these kind of posts.
So, what I wrote earlier stands. A future Messianic event - as described in the Septuagant, translated by Jews. The nation will look at Messiah who they pierced in the past, and mourn, recognizing it was Him. And the nation responds instantly.
Yes, I realize you don't agree now. But I wish you the best.
ampu